(a) Field of the Invention
The present invention relates to apparatus and method for transmitting and receiving a signal. More particularly, the present invention relates to a transmitting apparatus using frequency shift keying (FSK) modulation and a method thereof, and a receiving apparatus for demodulating a signal modulated according to FSK modulation and a method thereof.
(b) Description of the Related Art
Frequency shift keying (FSK) modulation has been receiving attention again as a method for supporting low power communication and medium to long distance communication.
A FSK modulation-based transmission method consumes a low amount of power and can be realized as a small transceiver. Accordingly, the FSK modulation-based transmission method has been adopted as a physical layer of international standard of a smart utility network (SUN) defined in IEEE 802.15.4 g.
The FSK modulation-based transmission method is a technology for transmitting a signal by modulating a signal through frequency shift. Accordingly, the FSK modulation-based transmission method is appropriate for a singular spectrum guaranteed environment and a low frequency environment.
Such an FSK modulation-based transmission method is used to transmit a simple digital signal or a simple analog signal. The FSK modulation-based transmission method, however, is not appropriate to realize a transceiver for transmitting a digital signal at a high transmission rate or for efficiently consuming power. Particularly, the FSK modulation-based transmission method has a limitation of reusing a frequency in a multinetwork-based system. That is, in a multinetwork-based system, it is very difficult to reduce distortion caused by multipaths or to reduce interference caused by multinetworks in various wireless environments with the FSK modulation-based transmission method due to interference vulnerability thereof.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.